Alex Atala of São Paulo, René Redzepi of Copenhagen and David Chang of New York

On his own, each chef in this trio is demanding, innovative, entertaining and charismatic. They also happen to be close buds, despite the vast distances that separate their restaurants. More important, in their combined iconoclastic approach to fine dining, they have transformed the image of the chef from distant aesthete to in-your-face dude. Atala, who runs D.O.M. in São Paulo, has enough tattoos to illustrate a Sistine kitchen. Chang, whose Momofuku fief in New York City is now a multinational empire, doesn't shy away from choice four-letter words. Redzepi--the creator of an exquisite and daring cuisine at Noma, in Copenhagen--approaches everything...